Problem
I need to add an Outlook Data File to my messages pane
Solution
Follow these steps to import the data file into Outlook:
In Outlook, open the File tab.
Navigate to the “Open & Export” menu.
Click the “Open Outlook Data File” button.
Browse to your Outlook Data File (.pst) and double-click it, or select it and click “OK”
Wait for Outlook to finish loading the contents, usually takes a few seconds but could take longer depending on the size of the file.
There will now be a new Mailbox option on your sidebar in Outlook’s main window, related to the mailbox or data file you just imported
To Remove The Mailbox From Your Sidebar
Right click the Mailbox name in your sidebar
Select “Close ‘{mailbox name}’”